Wrist watch including a reversibility device

ABSTRACT

The invention relates to a reversible watch housing (1) against which is provided on both sides a removable member (2, 2′) including the horns (3) of said housing (1). Each member (2, 2′) is connected to the watch housing (1) by attachment means arranged so that said member (2, 2′) can be locked to the watch housing (1) respectively in a first and second stable position. The removable member (2, 2′) can also be actuated for pivoting about its center by 180° along an axis perpendicular to the central axis of the watch housing (1) so as to move from one stable position to the other, each removable member (2, 2′) includes a bearing side (4), said bearing side (4) being maintained against a portion (5) located on the periphery of the watch housing (1), by an elastic member (6) provided inside the middle of said housing (1) and connected to the removable member (2, 2′) through an opening (7) located on the periphery of the watch housing (1). The opening (7) is formed so as to correspond with the rotation axis of the removable member (2, 2′). The removable member (2, 2′) can be released from one or the other stable positions in order to allow its rotation by 180° along the axis perpendicular to the central axis of the watch housing (1), the elastic member (6) acting on the removable member (2, 2′) in order to return the same into one or the other of its stable positions.

The present invention relates to horology, and more specifically amechanism for reversing the watch case relative to a strap.

Countless devices allowing a watch case to be reversed with respect to astrap already exist in the prior art. Most of these devices arecomplicated and are detrimental to the styling of the watch.

Nonetheless, there are some watches that have a reversibility device inwhich the components of the mechanism do not interfere with the cleanlines of the watch. One such mechanism is disclosed for example inpublication CH659167. This describes a wristwatch with two differentdisplays, one on each face, and which has a reversibility devicecomprising two removable elements on which the lugs of the watch arearranged. These removable elements are located either side of the watchcase and can be actuated to pivot through 180° at their center about ajournal on an axis perpendicular to the central axis of the watch casein order to orient either face of the watch according to the type ofdisplay the wearer of the watch wishes to show.

The watch case is locked relative to one of the ends of the strap byfirst and second balls arranged in first and second housings,respectively, one on either side of a rectangular part of the watchcase. These balls are acted on by a return spring which tends to engagethem in a hollow formed in the end of a rectangular loop in a positioncorresponding to the balls.

However, this form of locking creates a limitation in the geometricalshape of the watch case, since the latter has to have a rectangular partadjacent to each end of the watch strap.

Publication CH138929 discloses a wristwatch comprising two diametricallyopposite pivots fixed so as to project out of the watch case, and onwhich the strap attachments pivot. These attachments possess a curvaturein order to be able to conform to part of the circumference of the watchcase. However, this device has the drawback of having no locking system,and the watch case is held in position by the wearer's wrist only.

The object of the present invention is to provide a wristwatchcomprising an improved device for reversing the watch case with respectto the strap, which device is discrete and in perfect harmony with thestyling of the watch.

In accordance with the invention, this object is achieved by means of areversible watch case as claimed in claim 1 against which is located oneither side a removable element possessing the lugs of said case. Eachremovable element is connected to the watch case by fixing meansarranged in such a way that said element can be locked to the watch casein a first stable position and a second stable position. The removableelement is also actuatable to pivot at its center through 180° about anaxis perpendicular to the central axis of the watch case in order tomove from one of the stable positions to the other. Each removableelement comprises a contact side, this contact side being held against apart situated on the perimeter of the watch case by an elastic memberarranged inside the middle of said case and connected to the removableelement through an opening situated in the perimeter of the watch case.The opening is arranged in line with the axis of rotation of theremovable element, the removable element being disengageable from eitherof its stable positions in order to allow its rotation through 180°about the axis perpendicular to the central axis of the watch case, andthe elastic member acting on the removable element in order to return itto either of its stable positions.

The features of the invention will become more clearly apparent onreading a description of a number of embodiments offered purely by wayof example, no limitation being implied. The description refers to thediagrammatic figures in which:

FIG. 1 is an exploded perspective view of the watch case and of thereversibility device in a first embodiment,

FIG. 2 is a partial cross section through one of the removable elementsconnected, by the reversibility device, to the watch case, when saiddevice is locked,

FIG. 3 is a partial cross section through the removable element seen inFIG. 2 when the latter is in the disengaged position to allow it tobegin to be rotated with respect to the watch case,

FIG. 4 is a side view of the watch case without the removable element,

FIG. 5 is a detailed view of FIG. 4,

FIG. 6 is a partial cross section through one of the removable elements,in a second embodiment, when the reversibility device is locked,

FIG. 7 is a partial cross section through the removable element seen inFIG. 6 when the latter is in the disengaged position to allow it tobegin to be rotated with respect to the watch case.

In a first embodiment of the present invention (FIG. 1), the wristwatchcomprises a watch case (1) and two removable elements (2, 2′) on whichthe lugs (3) of the watch are arranged.

Each removable element (2, 2′) is connected to the watch case (1) byfixing means, the technical features of which will be described later,and which are arranged in such a way that said element (2, 2′) can belocked to the watch case (1) in a first stable position and a secondstable position. The removable element (2, 2′) is furthermore actuatableto pivot at its center through 180° about an axis perpendicular to thecentral axis of the watch case (1) in order to move from one of thestable positions to the other.

The watch case (1) possesses on its outer circumference twodiametrically opposite parts (5) which are ground so that the radius ofcurvature of each part (5) is slightly shorter than the radius ofcurvature of the outer circumference of the watch case (1). Eachremovable element (2, 2′) possesses a concave side (4) identical to theradius of curvature of each ground part (5) so that it can be arrangedto exactly fit the perimeter of said part (5). The thickness of theremovable element (2, 2′) is chosen in such a way that the element canblend into the outer circumference of the watch case (1) when theseremovable elements (2, 2′) are locked in stable positions.

The removable element (2, 2′) is locked against the ground part (5) ofthe watch case (1) via a flexible leaf (6) arranged inside the middle ofsaid case (1) (FIGS. 2 and 3). The ends of this leaf (6) bear againstthe inner circumference of the watch case (1).

Two elongate openings (7) (FIGS. 4 and 5) are arranged in the center ofeach ground part (5) in positions corresponding to the axis of rotationof the removable element (2, 2′). Each opening (7) is designed to takean elongate nub (8) connected to the removable element (2, 2′), this nub(8) being situated in the center of the concave side (4) of eachremovable element (2, 2′) and having an internal thread (9) in itscenter, in which a stud (10) for the cylindrical pivoting is screwed.The flexible leaf (6) has a bore (11) in its center, in which the pivotstud (10) is first arranged and then secured by a key (12).

The ends of the leaf (6) apply a certain stress to the innercircumference of the watch case (1) at their points of contact when thenub (8) is arranged inside the opening (7) so that the removable element(2, 2′) is held firmly against the part (5) of the watch case (1).

To reverse the watch case (1), the removable element (2, 2′) is pivotedthrough 180° about an axis perpendicular to the central axis of saidcase (1). This is made possible when the end of the strap connected tothe removable element (2, 2′) is pulled in order to bend the leaf spring(6) and disengage the nub (8) from the opening (7). The removableelement (2, 2′) can then be rotated about an axis perpendicular to thecentral axis of the watch case (1). In the course of this rotation, thesurface of the nub (8) of the removable element (2, 2′) is in permanentcontact with a circular-shaped flat (13) situated around the opening(7). After a 180° rotation, the nub (8) is back in a positioncorresponding to the opening (7) and, because of the action of the leafspring (6), fits once again inside the opening (7). The removableelement (2, 2′) is thus locked once again to the watch case (1).

In a second embodiment, the leaf spring (6) is replaced by a helicalcompression spring (6) (FIGS. 6 and 7). This spring (6) is arrangedaround the circumference of the central part of the pivot stud (10′). Inthis second embodiment, one of the ends of this stud (10′) has acircular base (15) against which the compression spring (6) presses,while the other end of the stud (10′) is ground and threaded so that itcan be screwed into the internal thread (9) of the nub (8) of theremovable element (2, 2′). The helical compression spring (6) is held inplace by a retaining plate (14) arranged against part of the innerperiphery of the watch case (1).

Operation of the reversibility system is identical to the firstembodiment. The helical spring (6) is compressed by the circular base(15) when the end of the strap connected to the removable element (2,2′) is pulled in order to disengage the nub (8) from the opening (7).Rotating the removable element (2, 2′) through 180° from the firststable position to the second is done exactly as in the firstembodiment.

It goes without saying that the invention is not limited to theembodiments described above by way of examples but rather that itencompasses all variants. For example, the shape of the reversible watchcase (1) can be oval or rectangular.

1. A reversible watch case (1) against which is located on either sidetwo removable elements (2, 2′) possessing lugs (3) of said case (1),each element (2, 2′) being connected to the watch case (1) by fixingmeans arranged in such a way that said element (2, 2′) can be locked tothe watch case (1) in a first stable position and a second stableposition, the removable element (2, 2′) also being actuatable to pivotat the removable element's center through 180.degree. about an axisperpendicular to a central axis of the watch case (1) in order to movefrom one of the stable positions to the other, which watch case ischaracterized in that each removable element (2, 2′) comprises a contactside (4), this contact side (4) being held against a part (5) situatedon a perimeter of the watch case (1) by an elastic member (6) arrangedinside the middle of said case (1) and connected to the removableelement (2, 2′) through an opening (7) situated in the perimeter of thewatch case (1), the opening (7) being arranged in line with the axis ofrotation of the removable element (2, 2′), the removable element (2, 2′)being disengageable from either of the removable element's stablepositions in order to allow its rotation through 180.degree. about theaxis perpendicular to the central axis of the watch case (1), and theelastic member (6) acting on the removable element (2, 2′) in order toreturn to either of the stable positions.
 2. The reversible watch case(1) as claimed in claim 1, characterized in that on the one hand theperimeter of the watch case (1) is circular, and on the other hand thecontact side (4) of the removable element (2, 2′) and the part (5)situated on the perimeter of the watch case (1) are concave and convex,respectively.
 3. The reversible watch case (1) as claimed in claim 2,characterized in that the radius of curvature of the convex part (5) ofthe reversible watch case (1) is approximately equal to the radius ofcurvature of the concave contact side (4) of the removable element (2,2′), and less than the radius of curvature of the external circumferenceof the watch case (1) in order to compensate for the thickness of theremovable element (2, 2′) so as to create an exactly circular watch case(1) when the removable elements (2, 2′) are arranged in either of thestable positions against the two convex parts (5) of the watch case (1).4. The reversible watch case (1) as claimed in claim 3, characterized inthat a nub (8) is arranged in the center of the concave side (4) of eachremovable element (2, 2′), the nub (8) being held in the opening (7),which acts as a housing, by the elastic member (6) in order to lock theremovable element (2, 2′) in either of the stable positions.
 5. Thereversible watch case (1) as claimed in claim 4, characterized in thatthe opening (7) and the nub (8) are elongate.
 6. The reversible watchcase (1) as claimed in claim 1, characterized in that the elastic member(6) is a flexible leaf, and the ends of said leaf (6) bear against theinside edge of the watch case (1).
 7. The reversible watch case (1) asclaimed in claim 1, characterized in that the elastic member (6) is ahelical compression spring.
 8. A watch strap comprising the reversiblewatch case (1) as claimed in any one of the preceding claims,characterized in that the ends of the strap are attached to theremovable elements (2, 2′).